GB182591A - Improvements in quick make and break electrical switches - Google Patents

Abstract

182,591. Shergold, F., and Edison Swan Electric Co., Ltd. April 16, 1921. Switches, quick-action, of the ironclad type, have the movable switch mechanism mounted on the hinged lid and the contact member guided on a post depending from the lid so as to move rectilinearly. The contact-member, which is held in the open and closed positions by a spring-controlled pin which is removed by the operating member when the spring has been adequately strained, comprises a sleeve 8 sliding on the post 7 and having arms 9 terminating in clamps for the fuse-holders 11. The clamps are interconnected by a pin 22 to which the ends of two springs 33, 34 are fastened, the other ends being connected to crank arms 31, 32 secured to the handle shafts which is mounted in the cover. A pair of links 20, 21 extend between the pin 22 and the operating shaft and have a slot connection with the pin and loose mounting on the shaft. Intermediate slots in the links accommodate a locking pin 23 controlled by a spring push-pin 26 so as, in the on and off positions of the switch, to engage recesses 28, 29 in a plate 27 extending from the cover and loosely surrounding the operating shaft to give rigidity. In closing the switch from the position shown, the springs are first strained, but the contact member is retained by the engagement of the pin 23 with one of the recesses until cam surfaces 36 on the inner parts of the crank members push the pin out of the recesses, whereupon a quick spring action follows. If the springs fail,. the cam surfaces first drive the pin to the end of the slots and then lock up with it rigidly so as. to drive the links, and consequently the contactmember, positively. A cam formation on the exterior of the handle shaft co-operates with a projection on the fixed portion of the casing to interlock the switch mechanism and cover.